Simplify the following expression: $q = \dfrac{6t}{-3t - 15}$ You can assume $t \neq 0$.
Explanation: Find the greatest common factor of the numerator and denominator. The numerator can be factored: $6t = (2\cdot3 \cdot t)$ The denominator can be factored: $-3t - 15 = - (3 \cdot t) - (3\cdot5)$ The greatest common factor of all the terms is $3$ Factoring out $3$ gives us: $q = \dfrac{(3)(2t)}{(3)(-t - 5)}$ Dividing both the numerator and denominator by $3$ gives: $q = \dfrac{2t}{-t - 5}$